Foundations of Corrective Exercise Science
What the science foundation actually tests
Corrective exercise rests on the idea that the body is a kinetic chain: a fault at the foot changes force at the knee, hip, and shoulder. Candidates must know the difference between local stabilizers (deep, segmental - transverse abdominis, multifidus, rotator cuff, deep neck flexors, gluteus medius) and global mobilizers (superficial, force-producing - rectus abdominis, erector spinae, latissimus dorsi, hamstrings, hip flexors). When a stabilizer becomes inhibited, a mobilizer substitutes - synergistic dominance.
The neurophysiology is heavily tested. The muscle spindle lies in the muscle belly, senses stretch velocity, and drives the stretch reflex (contraction). The Golgi tendon organ sits at the musculotendinous junction, senses tension, and produces autogenic inhibition (relaxation of that same muscle). Reciprocal inhibition is relaxation of the antagonist while the agonist contracts; altered reciprocal inhibition is the chronic version, where a tight agonist keeps its antagonist inhibited and weak.
Also know Davis's law (soft tissue remodels along lines of stress), Wolff's law (bone), the SAID principle, and the general adaptation syndrome.
Trap: items that swap spindle and GTO, or call foam rolling a "lengthening" technique - it is inhibitory, modulating tone.
Rule of thumb: 30 seconds. The stretch reflex is fast and defensive; holding past roughly 30 seconds lets GTO-mediated autogenic inhibition override it, which is why SMR and static holds are prescribed at 30–60 seconds.
Worked example: a client with a tight psoas and an underactive gluteus maximus. The hip flexor keeps the glute inhibited through altered reciprocal inhibition, so you inhibit and lengthen the hip flexor first - you never stretch the weak glute.